Welcome, Jiong Tao.
I hope that you find at least part of the information you are
seeking here on the CONCH-L listserver.
You may already have found the articles on Nesiocypraea in the
on-line articles of Griffiths' THE COWRY which are located at
http://www.geocities.com/~makuabob/ --- the Archive site of my
homepage called THE CAPTURED COWRY.
I also recall some references to this group in the on-line version
of Lindsey Grove's Index of Cypraeacean & Triviacean Literature,
which is in this same site.
Also, there is nearly 32 years' worth of cowry-related articles
from the Hawaiian Malacological Society's HAWAIIAN SHELL NEWS.
Again, glad to see you in the group.
Aloha (Hawaiian for 'hello', 'goodbye', and several other nice things),
Bob Dayle (Also Known As 'makuabob')